Miata sway bar bolt missing

Hello everyone! As the title says I have a sway bar end link bolt missing. How did it become missing? Well I was letting the car down off the jack after doing some exhaust work, and the pressure let out too fast. The car came down hard on the right side (left side still on a jack stand). I didn't think too much of it until I went for a test drive. I was hearing a hollow sounding thump from the right side while driving normal and during turns. I instantly knew it was the suspension. While turning into my driveway the thump turned into a snap. Once in the garage I inspected the suspension and found the swaybar bolt that meets the end link was completely gone. It is too dark to search for debris in the driveway and street.

Well, I need a new bolt, nut and any washers associated with the set up. Should I take the left side assembly off and take it to Ace hardware or do I have to get a "real" automotive part. Any feedback would be appreciated.

Man, just a slam off the jack backed it out? Sounds like it was loose before you ever put the car in the air. If you're going to look for the thing, I suggest looking for it in the place between the last time it went "thump" and the first time it went "snap".

YMMV, but I recommend finding the real parts. A lot of the hardware store stuff is just strong enough to keep the light fixture on the front porch, even if you can find one that fits. And all the Miatas around here..somebody ought to have a real one laying around in a tray that they'd give you for free.

I haven't had a problem with Ace Hardware hardware parts on my cars. Just make sure you get a decent grade instead of the stuff that's barely better than peanut butter.

I wouldn't be afraid to use a hardware store bolt there. Get a metric one and get a higher grade (remember metric grades are different, you're looking for grade 10 if memory serves me) and you should be fine.

Yeah problem solved and thanks for all the advice. I went to Advance auto or one of those chains and found a M10 1.25 40mm bolt that seems to work fine. Only problem is I had to buy 10 bolts, 10 nuts and 10 washers, they did not have what i needed in a single pack! Oh well, $10 isn't much for having a working car now.

Grade 8 bolts should hold...any Tractor Supply should have them.

That's where you have to be careful. Grade 8 is an SAE thing. Metric bolts come in 8.8 (roughly equivalent to SAE Grade 5) and 10.9 (SAE Grade 8). Just for fun, stainless metric uses A-2.

Short form: Picking up a metric 8.8 bolt is not the same as a "standard" grade 8 bolt.

This fix is temporary until I can salvage some off a junk miata. It seems my bolt may be a SAE 5 being a metric with 8.8 stamped on it. It is the sway bar so not much force is carried by one bolt. I also don't drive hard. If it does fail before I can source the right part, it won't leave me stranded.

Agreed, although I think the forces involved might be a bit higher than you think. I just wanted to clarify the difference between "grade 8" and 8.8.

I think you'll have many other parts break prior to a grade 5 equivalent bolt shearing. My 2cents- also having a sway bar bolt break or disappear isn't going to kill you.